So I understand that you just don't want people to resell your creation, is that it? Because putting it in an opensource game means people have direct access to the assets, like the FantasyHex tile set used here: https://github.com/yairm210/Unciv/tree/master/android/Images/TileSets/FantasyHex (I am in fact planning to use your tileset in Unciv just like this)
Of course, Unciv is also being distributed as a binary for download and play on desktop PC and Android phone.